By Kathryn Doyle
NEW YORK (Reuters Health) - A daily dose of ospemifene, an estrogen-like drug, helped lessen pain during intercourse caused by vaginal atrophy in postmenopausal women, in a new study.
"This appears to be a good alternative for women who can't or choose not to use estrogen therapy," Dr. JoAnn Pinkerton, medical director of the Midlife Health Center at the University of Virginia in Charlottesville, told Reuters Health.
The trial, which was funded by the drug's manufacturer QuatRx pharmaceuticals, included 600 women aged 40 to 80 who had been diagnosed with atrophy and reported moderate to severe pain during sex.
Researchers randomly assigned half of the women to take 60 milligrams of ospemifene in tablet form daily for 12 weeks, while the other half took a placebo.
At the end of the study, women taking the drug had lower vaginal pH - which is abnormally high with vaginal atrophy - and reported significantly less pain during sex. They also used less lubricant, which indicated sex was more comfortable, according to results published in the journal Menopause.
"It appears to be as effective as a low-dose oral estrogen," lead author Dr. David Portman told Reuters Health by email.
Roughly half of postmenopausal women experience vaginal atrophy, caused by a dip in estrogen levels. Unlike other symptoms that are common during menopause, such as hot flashes, vaginal atrophy does not go away after a few years, and can get worse if untreated.
In her practice, which is almost entirely postmenopausal women, Pinkerton has seen some patients cease having sex entirely. "It can really cause relationship problems," said Pinkerton, who was not involved in the study.
The most common, bothersome symptoms of vaginal atrophy are dryness and pain during sex, according to Portman, and over-the-counter lubricant doesn't always help.
"The tissue is easily injured and tears and is subject to infection due to pH and cellular changes," said Portman, director of the Columbus Center for Women's Health Research in Ohio. "Lubricants only make sex more slippery, but do not eliminate these painful injuries to the tissue."
Portman and other study authors have consulted for Shionogi Inc, a partner of QuatRx.
Estrogen pills can alleviate atrophy, but may also increase the risk of breast cancer - a chance many postmenopausal women don't want to take.
That's especially true for women who have already had certain types of breast cancers that are fueled by hormones.
"After a diagnosis of breast cancer, women sometimes struggle with resumption of sexuality," Pinkerton said. If they have vaginal atrophy, the only current treatment options outside of estrogen pills are topical creams, tablets and moisturizers, which are less effective and cost about $60 per month because they have no generic forms.
Oral estrogen can affect all areas the hormone acts on, including the breasts, uterus, vagina and bones, and can be beneficial in one area but harmful in another.
Instead of containing actual estrogen, ospemifene is a type of drug called a selective estrogen receptor modulator (SERM), which can selectively act on some organs and not others. Ospemifene targets the cells of the vagina and appears not to affect the uterus or breasts.
"My prediction is that it will not be as good as estrogen (for vaginal atrophy) but will be significantly better than vaginal moisturizers," Pinkerton said.
The most notable side effect of the drug was more hot flashes, but they didn't seem severe, she said.
Other trials have demonstrated the effectiveness of ospemifene in treating pain during sex as well as dryness and other symptoms of vaginal atrophy.
If the U.S. Food and Drug Administration approves the drug by its deadline on February 26, ospemifene is set to be available in the U.S. later in 2013. It's unclear how much it will cost, but Pinkerton said it should be cheaper than some current options for vaginal atrophy.
STUDY: http://bit.ly/VZsw0t Menopause, online January 28, 2013.